The present invention relates to an apparatus and a method for controlling automatic stop of an internal combustion engine. Particularly, the present invention pertains to a technique that automatically stops an internal combustion engine if the engine is running under a predetermined running state when the vehicle is not running.
An economy running system (hereinafter referred to as an eco-run system) is adapted to a prior-art internal combustion engine of a vehicle. The system automatically stops the engine when the vehicle is not running, which improves fuel economy. The system automatically stops the engine when the vehicle stops, for example, at an intersection, and automatically starts the engine by rotating a starter motor, such that the engine is automatically started to start the vehicle, when the vehicle is operated to start. Japanese Laid-Open Patent Publication No. 2000-337188 discloses the above-mentioned eco-run system. The system prohibits the automatic stop of the engine if there is no historical data indicating that the vehicle has moved after the engine is started. Accordingly, the frequency of the automatic stop of the engine is reduced, which prevents the performance of the battery from being deteriorated by insufficient charge and deters deterioration of the starter motor.
The system disclosed in the publication, however, always prohibits the automatic stop of the engine if there is no traveling historical data after the start of the engine. Therefore, fuel economy cannot be improved.
Accordingly, it is an objective of the present invention to provide an apparatus and a method for controlling automatic stop of an internal combustion engine that increases the frequency of the automatic stop of the engine, thereby improving fuel economy.
To achieve the above objective, the present invention provides an automatic stop controlling apparatus for automatically stopping an engine. The engine is mounted on a vehicle and is coupled to an automatic transmission. The automatic transmission has a plurality of shift positions. The apparatus includes a sensor for detecting the state of the vehicle, and a controller for controlling the engine. When it is judged that predetermined automatic stop conditions are satisfied based on the state of the vehicle, the controller stops the engine. The controller changes the automatic stop conditions in accordance with the shift position of the automatic transmission. The automatic stop condition to be changed is related to at least one of traveling historical data of the vehicle and the road condition.
The present invention also provides a method for controlling an automatic stop of an engine. The engine is mounted on a vehicle and is coupled to an automatic transmission. The automatic transmission has a plurality of shift positions. The method includes detecting the state of the vehicle, stopping the engine when it is judged that predetermined automatic stop conditions are satisfied based on the detected state of the vehicle, and changing the automatic stop conditions in accordance with the shift position of the automatic transmission. The automatic stop condition to be changed is related to at least one of traveling historical data of the vehicle and the road condition.
The present invention further provides a medium, which is readable by a computer and has within it a program for automatically stopping an engine. The engine is mounted on a vehicle and is coupled to an automatic transmission. The automatic transmission has a plurality of shift positions. The program causes the computer to execute the following procedures: detecting the state of the vehicle; stopping the engine when it is judged that predetermined automatic stop conditions are satisfied based on the detected state of the vehicle; and changing the automatic stop conditions in accordance with the shift position of the automatic transmission. The automatic stop condition to be changed is related to at least one of traveling historical data of the vehicle and the road condition.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.